<template>
	<view class="u-upload" :style="[$u.addStyle(customStyle)]">
		<view class="u-upload__wrap">
			<template v-if="previewImage">
				<view class="u-upload__wrap__preview" v-for="(item, index) in lists" :key="index">
					<image
						v-if="(item.isImage || (item.type && item.type === 'image')) && !item.isVideo"
						:src="item.thumb || item.url"
						:mode="imageMode"
						class="u-upload__wrap__preview__image"
						@tap="onPreviewImage(item, index)"
						:style="[
							{
								width: $u.addUnit(width),
								height: $u.addUnit(height)
							}
						]"
					/>
					<view
						v-else
						class="u-upload__wrap__preview__other"
						:style="[
							{
								width: $u.addUnit(width),
								height: $u.addUnit(height)
							}
						]"
					>
						<u-icon color="#80CBF9" size="52" :name="item.isVideo || (item.type && item.type === 'video') ? 'movie' : 'folder'"></u-icon>
						<text class="u-upload__wrap__preview__other__text">{{ item.isVideo || (item.type && item.type === 'video') ? '视频' : '文件' }}</text>
					</view>
					<view class="u-upload__status" v-if="item.status === 'uploading' || item.status === 'failed'">
						<view class="u-upload__status__icon">
							<u-icon v-if="item.status === 'failed'" name="close-circle" color="#ffffff" size="50" />
							<u-loading-icon size="44" mode="circle" color="#ffffff" v-else />
						</view>
						<text v-if="item.message" class="u-upload__status__message">{{ item.message }}</text>
					</view>
					<view class="u-upload__deletable" v-if="item.status !== 'uploading' && (deletable || item.deletable)" @tap.stop="deleteItem(index)">
						<view class="u-upload__deletable__icon">
							<u-icon name="close" color="#ffffff" size="20"></u-icon>
						</view>
					</view>
					<view class="u-upload__success" v-if="item.status === 'success'">
						<!-- #ifdef APP-NVUE -->
						<image :src="successIcon" class="u-upload__success__icon"></image>
						<!-- #endif -->
						<!-- #ifndef APP-NVUE -->
						<view class="u-upload__success__icon">
							<u-icon name="checkmark" color="#ffffff" size="12"></u-icon>
						</view>
						<!-- #endif -->
					</view>
				</view>
			</template>

			<template v-if="isInCount">
				<view v-if="$slots.default || $slots.$default" @tap="chooseFile">
					<slot />
				</view>
				<view
					v-else
					class="u-upload__button"
					:hover-class="!disabled ? 'u-upload__button--hover' : ''"
					hover-stay-time="150"
					@tap="chooseFile"
					:class="[disabled && 'u-upload__button--disabled']"
					:style="[
						{
							width: $u.addUnit(width),
							height: $u.addUnit(height)
						}
					]"
				>
					<u-icon :name="uploadIcon" size="26" :color="uploadIconColor"></u-icon>
					<text v-if="uploadText" class="u-upload__button__text">{{ uploadText }}</text>
				</view>
			</template>
		</view>
	</view>
</template>

<script>
import { chooseFile } from './utils';
import mixin from './mixin.js';
import props from './props.js';

/**
 * upload 上传
 * @description 该组件用于上传图片场景
 * @tutorial https://uviewui.com/components/upload.html
 * @property {String}			accept				接受的文件类型, 可选值为all media image file video （默认 'image' ）
 * @property {String | Array}	capture				图片或视频拾取模式，当accept为image类型时设置capture可选额外camera可以直接调起摄像头（默认 ['album', 'camera'] ）
 * @property {Boolean}			compressed			当accept为video时生效，是否压缩视频，默认为true（默认 true ）
 * @property {String}			camera				当accept为video时生效，可选值为back或front（默认 'back' ）
 * @property {Number}			maxDuration			当accept为video时生效，拍摄视频最长拍摄时间，单位秒（默认 60 ）
 * @property {String}			uploadIcon			上传区域的图标，只能内置图标（默认 'camera-fill' ）
 * @property {String}			uploadIconColor		上传区域的图标的字体颜色，只能内置图标（默认 #D3D4D6 ）
 * @property {Boolean}			useBeforeRead		是否开启文件读取前事件（默认 false ）
 * @property {Boolean}			previewFullImage	是否显示组件自带的图片预览功能（默认 true ）
 * @property {String | Number}	maxCount			最大上传数量（默认 52 ）
 * @property {Boolean}			disabled			是否启用（默认 false ）
 * @property {String}			imageMode			预览上传的图片时的裁剪模式，和image组件mode属性一致（默认 'aspectFill' ）
 * @property {String}			name				标识符，可以在回调函数的第二项参数中获取
 * @property {Array}			sizeType			所选的图片的尺寸, 可选值为original compressed（默认 ['original', 'compressed'] ）
 * @property {Boolean}			multiple			是否开启图片多选，部分安卓机型不支持 （默认 false ）
 * @property {Boolean}			deletable			是否展示删除按钮（默认 true ）
 * @property {String | Number}	maxSize				文件大小限制，单位为byte （默认 Number.MAX_VALUE ）
 * @property {Array}			fileList			显示已上传的文件列表
 * @property {String}			uploadText			上传区域的提示文字
 * @property {String | Number}	width				内部预览图片区域和选择图片按钮的区域宽度（默认 80 ）
 * @property {String | Number}	height				内部预览图片区域和选择图片按钮的区域高度（默认 80 ）
 * @property {Object}			customStyle			组件的样式，对象形式
 * @event {Function} afterRead		读取后的处理函数
 * @event {Function} beforeRead		读取前的处理函数
 * @event {Function} oversize		文件超出大小限制
 * @event {Function} clickPreview	点击预览图片
 * @event {Function} delete 		删除图片
 * @example <u-upload :action="action" :fileList="fileList" ></u-upload>
 */
export default {
	name: 'u-upload',
	mixins: [uni.$u.mpMixin, uni.$u.mixin, mixin, props],
	data() {
		return {
			// #ifdef APP-NVUE
			successIcon:
				'',
			// #endif
			lists: [],
			isInCount: true
		};
	},
	watch: {
		// 监听文件列表的变化，重新整理内部数据
		fileList: {
			immediate: true,
			handler() {
				this.formatFileList();
			}
		}
	},
	methods: {
		formatFileList() {
			const { fileList = [], maxCount } = this;
			const lists = fileList.map(item =>
				Object.assign(Object.assign({}, item), {
					// 如果item.url为本地选择的blob文件的话，无法判断其为video还是image，此处优先通过accept做判断处理
					isImage: this.accept === 'image' || uni.$u.test.image(item.url || item.thumb),
					isVideo: this.accept === 'video' || uni.$u.test.video(item.url || item.thumb),
					deletable: typeof item.deletable === 'boolean' ? item.deletable : this.deletable
				})
			);
			this.lists = lists;
			this.isInCount = lists.length < maxCount;
		},
		chooseFile() {
			const { maxCount, multiple, lists, disabled } = this;
			if (disabled) return;
			// 如果用户传入的是字符串，需要格式化成数组
			let capture;
			try {
				capture = uni.$u.test.array(this.capture) ? this.capture : this.capture.split(',');
			} catch (e) {
				capture = [];
			}
			chooseFile(
				Object.assign(
					{
						accept: this.accept,
						multiple: this.multiple,
						capture: capture,
						compressed: this.compressed,
						maxDuration: this.maxDuration,
						sizeType: this.sizeType,
						camera: this.camera
					},
					{
						maxCount: maxCount - lists.length
					}
				)
			)
				.then(res => {
					this.onBeforeRead(multiple ? res : res[0]);
				})
				.catch(error => {
					this.$emit('error', error);
				});
		},
		// 文件读取之前
		onBeforeRead(file) {
			const { beforeRead, useBeforeRead } = this;
			let res = true;
			// beforeRead是否为一个方法
			if (uni.$u.test.func(beforeRead)) {
				// 如果用户定义了此方法，则去执行此方法，并传入读取的文件回调
				res = beforeRead(file, this.getDetail());
			}
			if (useBeforeRead) {
				res = new Promise((resolve, reject) => {
					this.$emit(
						'beforeRead',
						Object.assign(
							Object.assign(
								{
									file
								},
								this.getDetail()
							),
							{
								callback: ok => {
									ok ? resolve() : reject();
								}
							}
						)
					);
				});
			}
			if (!res) {
				return;
			}
			if (uni.$u.test.promise(res)) {
				res.then(data => this.onAfterRead(data || file));
			} else {
				this.onAfterRead(file);
			}
		},
		getDetail(index) {
			return {
				name: this.name,
				index: index == null ? this.fileList.length : index
			};
		},
		onAfterRead(file) {
			const { maxSize, afterRead } = this;
			const oversize = Array.isArray(file) ? file.some(item => item.size > maxSize) : file.size > maxSize;
			if (oversize) {
				this.$emit(
					'oversize',
					Object.assign(
						{
							file
						},
						this.getDetail()
					)
				);
				return;
			}
			if (typeof afterRead === 'function') {
				afterRead(file, this.getDetail());
			}
			this.$emit(
				'afterRead',
				Object.assign(
					{
						file
					},
					this.getDetail()
				)
			);
		},
		deleteItem(index) {
			this.$emit(
				'delete',
				Object.assign(Object.assign({}, this.getDetail(index)), {
					file: this.fileList[index]
				})
			);
		},
		// 预览图片
		onPreviewImage(item, index) {
			if (!item.isImage || !this.previewFullImage) return;
			if (this.isClickPreview) {
				this.$emit('clickPreview', Object.assign({}, item), index);
				return;
			}
			uni.previewImage({
				// 先filter找出为图片的item，再返回filter结果中的图片url
				urls: this.lists.filter(item => this.accept === 'image' || uni.$u.test.image(item.url || item.thumb)).map(item => item.url || item.thumb),
				current: item.url || item.thumb,
				fail() {
					uni.$u.toast('预览图片失败');
				}
			});
		},
		onPreviewVideo(event) {
			if (!this.data.previewFullImage) return;
			const { index } = event.currentTarget.dataset;
			const { lists } = this.data;
			wx.previewMedia({
				sources: lists
					.filter(item => isVideoFile(item))
					.map(item =>
						Object.assign(Object.assign({}, item), {
							type: 'video'
						})
					),
				current: index,
				fail() {
					uni.$u.toast('预览视频失败');
				}
			});
		},
		onClickPreview(event) {
			const { index } = event.currentTarget.dataset;
			const item = this.data.lists[index];
			this.$emit('clickPreview', Object.assign(Object.assign({}, item), this.getDetail(index)));
		}
	}
};
</script>

<style lang="scss" scoped>
@import '../../libs/css/components.scss';
$u-upload-preview-border-radius: 2px !default;
$u-upload-preview-margin: 0 8px 8px 0 !default;
$u-upload-image-width: 80px !default;
$u-upload-image-height: $u-upload-image-width;
$u-upload-other-bgColor: rgb(242, 242, 242) !default;
$u-upload-other-flex: 1 !default;
$u-upload-text-font-size: 11px !default;
$u-upload-text-color: $u-tips-color !default;
$u-upload-text-margin-top: 2px !default;
$u-upload-deletable-right: 0 !default;
$u-upload-deletable-top: 0 !default;
$u-upload-deletable-bgColor: rgb(55, 55, 55) !default;
$u-upload-deletable-height: 14px !default;
$u-upload-deletable-width: $u-upload-deletable-height;
$u-upload-deletable-boder-bottom-left-radius: 100px !default;
$u-upload-deletable-zIndex: 3 !default;
$u-upload-success-bottom: 0 !default;
$u-upload-success-right: 0 !default;
$u-upload-success-border-style: solid !default;
$u-upload-success-border-top-color: transparent !default;
$u-upload-success-border-left-color: transparent !default;
$u-upload-success-border-bottom-color: $u-success !default;
$u-upload-success-border-right-color: $u-upload-success-border-bottom-color;
$u-upload-success-border-width: 9px !default;
$u-upload-icon-top: 0px !default;
$u-upload-icon-right: 0px !default;
$u-upload-icon-h5-top: 1px !default;
$u-upload-icon-h5-right: 0 !default;
$u-upload-icon-width: 16px !default;
$u-upload-icon-height: $u-upload-icon-width;
$u-upload-success-icon-bottom: -10px !default;
$u-upload-success-icon-right: -10px !default;
$u-upload-status-right: 0 !default;
$u-upload-status-left: 0 !default;
$u-upload-status-bottom: 0 !default;
$u-upload-status-top: 0 !default;
$u-upload-status-bgColor: rgba(0, 0, 0, 0.5) !default;
$u-upload-status-icon-Zindex: 1 !default;
$u-upload-message-font-size: 12px !default;
$u-upload-message-color: #ffffff !default;
$u-upload-message-margin-top: 5px !default;
$u-upload-button-width: 80px !default;
$u-upload-button-height: $u-upload-button-width;
$u-upload-button-bgColor: rgb(244, 245, 247) !default;
$u-upload-button-border-radius: 2px !default;
$u-upload-botton-margin: 0 8px 8px 0 !default;
$u-upload-text-font-size: 11px !default;
$u-upload-text-color: $u-tips-color !default;
$u-upload-text-margin-top: 2px !default;
$u-upload-hover-bgColor: rgb(230, 231, 233) !default;
$u-upload-disabled-opacity: 0.5 !default;

.u-upload {
	@include flex(column);
	flex: 1;

	&__wrap {
		@include flex;
		flex-wrap: wrap;
		flex: 1;

		&__preview {
			border-radius: $u-upload-preview-border-radius;
			margin: $u-upload-preview-margin;
			position: relative;
			overflow: hidden;
			@include flex;

			&__image {
				width: $u-upload-image-width;
				height: $u-upload-image-height;
			}

			&__other {
				width: $u-upload-image-width;
				height: $u-upload-image-height;
				background-color: $u-upload-other-bgColor;
				flex: $u-upload-other-flex;
				@include flex(column);
				justify-content: center;
				align-items: center;

				&__text {
					font-size: $u-upload-text-font-size;
					color: $u-upload-text-color;
					margin-top: $u-upload-text-margin-top;
				}
			}
		}
	}

	&__deletable {
		position: absolute;
		top: $u-upload-deletable-top;
		right: $u-upload-deletable-right;
		background-color: $u-upload-deletable-bgColor;
		height: $u-upload-deletable-height;
		width: $u-upload-deletable-width;
		@include flex;
		border-bottom-left-radius: $u-upload-deletable-boder-bottom-left-radius;
		align-items: center;
		justify-content: center;
		z-index: $u-upload-deletable-zIndex;

		&__icon {
			position: absolute;
			transform: scale(0.7);
			top: $u-upload-icon-top;
			right: $u-upload-icon-right;
			/* #ifdef H5 */
			top: $u-upload-icon-h5-top;
			right: $u-upload-icon-h5-right;
			/* #endif */
		}
	}

	&__success {
		position: absolute;
		bottom: $u-upload-success-bottom;
		right: $u-upload-success-right;
		@include flex;
		// 由于weex(nvue)为阿里巴巴的KPI(部门业绩考核)的laji产物，不支持css绘制三角形
		// 所以在nvue下使用图片，非nvue下使用css实现
		/* #ifndef APP-NVUE */
		border-style: $u-upload-success-border-style;
		border-top-color: $u-upload-success-border-top-color;
		border-left-color: $u-upload-success-border-left-color;
		border-bottom-color: $u-upload-success-border-bottom-color;
		border-right-color: $u-upload-success-border-right-color;
		border-width: $u-upload-success-border-width;
		align-items: center;
		justify-content: center;
		/* #endif */

		&__icon {
			/* #ifndef APP-NVUE */
			position: absolute;
			transform: scale(0.7);
			bottom: $u-upload-success-icon-bottom;
			right: $u-upload-success-icon-right;
			/* #endif */
			/* #ifdef APP-NVUE */
			width: $u-upload-icon-width;
			height: $u-upload-icon-height;
			/* #endif */
		}
	}

	&__status {
		position: absolute;
		top: $u-upload-status-top;
		bottom: $u-upload-status-bottom;
		left: $u-upload-status-left;
		right: $u-upload-status-right;
		background-color: $u-upload-status-bgColor;
		@include flex(column);
		align-items: center;
		justify-content: center;

		&__icon {
			position: relative;
			z-index: $u-upload-status-icon-Zindex;
		}

		&__message {
			font-size: $u-upload-message-font-size;
			color: $u-upload-message-color;
			margin-top: $u-upload-message-margin-top;
		}
	}

	&__button {
		@include flex(column);
		align-items: center;
		justify-content: center;
		width: $u-upload-button-width;
		height: $u-upload-button-height;
		background-color: $u-upload-button-bgColor;
		border-radius: $u-upload-button-border-radius;
		margin: $u-upload-botton-margin;
		/* #ifndef APP-NVUE */
		box-sizing: border-box;
		/* #endif */

		&__text {
			font-size: $u-upload-text-font-size;
			color: $u-upload-text-color;
			margin-top: $u-upload-text-margin-top;
		}

		&--hover {
			background-color: $u-upload-hover-bgColor;
		}

		&--disabled {
			opacity: $u-upload-disabled-opacity;
		}
	}
}
</style>
